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Microscopic colitis (MC), encompassing collagenous colitis and lymphocytic colitis, is featured by chronic diarrhea, normal-looking endoscopic findings and unique microscopic appearance. After reviewing biopsied nonspecific colitis, we propose the third type of MC: colitis nucleomigrans (CN). Histopathological criteria of CN included: (i) chained nuclear migration to the middle part of the surface-lining columnar epithelium; (ii) apoptotic nuclear debris scattered below the nuclei; and (iii) mild/moderate chronic inflammation in the lamina propria. Thirty-three patients (M:F = 20:13; median age 63 years, range 17-88) fulfilled our criteria. Seven cases demonstrated MC-like clinical/endoscopic features. Mucosal reddening with or without erosion/aphtha was endoscopically observed in the remaining 26 cases with inflammatory bowel disease (IBD)-like features: occult/gross hematochezia seen in 19, abdominal pain in two and mucin secretion in two. Cleaved caspase-3-immunoreactive apoptotic debris appeared more frequently in IBD-like CN than in MC-like CN, while CD8-positive intraepithelial lymphocytes comparably appeared in both. Proton pump inhibitors (PPIs) were administered in five (71%) cases with MC-like features, and in three diarrhea improved after drug cessation. In IBD-like CN cases, eight (31%) received PPIs. Four patients received chemotherapy against malignancies. Four patients associated immune-related disorders. Microscopic appearance of CN also appeared in a remission state of ulcerative colitis (12/20 lesions).

The porosity and effective thermal conductivity, which were measured simultaneously, changed owing to expansion during hydrogen absorption and contraction during hydrogen desorption. The metal hydride used in the experiment was a newly developed nano-structured FeTi (n-FeTi) by mechanical alloying. The porosity was measured by directly observing the changes in the volume of a metal hydride packed bed under free expansion. In the authors' previous study of LaNi5, the volume of the packed bed gradually increased, whereas the total volume of the n-FeTi packed bed decreased with increase in the cycles of expansion and contraction. The effective thermal conductivity measurements of the metal hydride packed bed were carried out using a cylindrical device with heating from a central heater. The results showed that the effective thermal conductivity of n-FeTi changes from 0.4 to 1.1 W/mK with rise in reacted fraction and decrease in porosity.

Inframalleolar (IM) bypass has been reported to demonstrate acceptable patency and limb salvage in patients with chronic limb-threatening ischemia. However, wound healing after IM bypass and comparisons between pedal artery (PA) bypass and pedal branch artery (PBA) bypass are lacking.We reviewed prospectively collected data from 208 consecutive patients after IM bypass performed over a period of 6 years. Patients were divided into two groups based on the distal anastomotic artery: the PA group (dorsal pedis artery or common plantar artery) and the PBA group (medial tarsal, lateral tarsal, medial plantar, and lateral plantar artery). The primary outcome was wound healing, and secondary outcomes included loss of patency and limb and life prognosis.Of the 208 patients, 174 (74%) had PA bypass, whereas 34 (16%) had PBA bypass. Patients in the PBA group were significantly younger than those in the PA group (69 ± 7 vs 73 ± 9; P = .03). Although early (30-day) graft failure was more common in the PBA group, late clinical outcomes, including the wound healing rate (79% in the PA group and 84% in the PBA group; P = .74), were similar between the two groups. The Global Limb Anatomic Staging System IM grade (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.58-0.93; P = .006); wound, ischemia, and foot infection wound grade (HR, 0.67; 95% CI, 0.51-0.89; P .01); and wound, ischemia, and foot infection foot infection grade (HR, 0.79; 95% CI, 0.65-0.96; P = .02) were independent predictors of wound healing.The current study revealed that wound healing in patients after PBA bypass was acceptable and comparable with that after PA bypass. In the modern era, including a high prevalence of infrapopliteal angioplasty, our results could provide useful information to clinicians in actual clinical settings. Moreover, PBA bypass may be an alternative revascularization procedure to avoid major amputation when the PA is occluded, such as in the global vascular guideline IM P2 grade. Prospective multicenter larger studies are warranted to confirm the findings of this study and to compare PBA bypass and IM endovascular treatment in patients with anatomical no-option chronic limb-threatening ischemia.

A 76-year-old man with epigastric pain developed 1 month earlier was referred to our department for additional screening and treatment after abdominal ultrasound revealed a mass shadow in the pancreatic head and liver. Blood biochemistry revealed signs of mild jaundice and hepatic dysfunction. Abdominal contrast-computed tomography revealed an irregular hypodense mass with poor enhancement in the pancreatic head and several hypodense nodules in the liver. Endoscopic examination revealed duodenal infiltration signs. The biopsied duodenal mucosa contained atypical cells with high nuclear-to-cytoplasmic ratios; the cells stained positive for CD56, chromogranin, and synaptophysin, and the Ki-67 index was 90%. Accordingly, pancreatic neuroendocrine carcinoma (PanNEC) was diagnosed. Platinum-based chemotherapy (6 courses) and streptozotocin (10 courses) were adopted as the first- and second-line regimens, respectively. However, the patient showed progressive disease (PD). Pembrolizumab was added as a third-line regimen (13 courses) after confirming PanNEC with high microsatellite instability (MSI-high). Despite a temporary partial response (PR), the patient showed PD by the end of the 13 courses and died 1 year and 7 months after diagnosis. Although there is no established PanNEC therapy, those with MSI-high may respond favorably to pembrolizumab. Therefore, we should ascertain the MSI status of any PanNEC in routine practice.

This paper proposes a method to improve ride comfort for a vehicle concerning an active suspension. The purpose of active suspension is to suppress the vibration of the vehicle body. The variation of two parameters; sprung mass and tire stiffness, deteriorate ride comfort because the vibration of the vehicle body depends on them. It is necessary to design a controller corresponding to the variations of these parameters. We apply a gain scheduled control for the sprung mass. The control is scheduled by the measurements of some parameters. We estimate the sprung mass using Square Root Unscented Kalman Filter to apply the gain scheduled control. On the other hand, robust control is applied for the tire stiffness. Then, we formulate the active suspension with uncertain parameters as a finite of linear matrix inequalities by using polytopic representation. The uncertainties are put into one matrix using descriptor representation to simply design the controller. We illustrate the effectiveness of the proposed method by simulation and evaluation based on International Organization of Standardization 2631–1.

A popliteal artery aneurysm is one of the most common peripheral arterial aneurysms. These aneurysms can cause distal embolization and thrombosis, leading to limb loss. However, their rupture is unusual. Here we report a case in which a popliteal aneurysm with chronic occlusion at its outflow artery developed a nonfatal, painful rupture. We performed only coil embolization of the proximal artery, and the aneurysm was successfully excluded. After the procedure, collateral circulation was maintained. No ischemic symptoms such as intermittent claudication or pain at rest were observed. This approach may be useful in treating similar cases.

Background Stent-stone complex (SSC) formation is one of the complications of endoscopic biliary stent placement. This study aimed to clarify the clinical characteristics and risk factors for SSC formation following plastic stent (PS) placement in patients with common bile duct (CBD) stones. Methods We retrospectively reviewed the charts of 78 patients with CBD stones who had undergone 107 biliary stent placements as palliative treatment. Demographic, historical, and stent-related data were collected and analyzed. Results At PS removal, SSC formations were observed in 18% of the 107 cases (SSC group) studied and not in the remaining 82% (non-SSC group). The duration of PS placement was significantly longer in the SSC group. The increase in CBD diameter during the stenting period as well as the incidence of cholangitis at PS removal was significantly greater in the SSC group. Multivariate analysis identified long-term (≥301 days) PS placement and the increase in CBD diameter during the stenting period as independent factors for SSC formation. Conclusions Long-term PS placement induces a risk of SSC formation in patients with CBD stones. The increase in diameter of CBD during the period of PS placement is a predictive factor for SSC formation in this situation.

The effective thermal conductivity of a metal hydride packed bed was calculated by considering the influence of expansion during hydrogen absorption and contraction during hydrogen desorption. The porosity was calculated using an experimental formula developed by direct observation, which was used in combination with other referenced methods. However, none of the methods could express the reported experimental value response to pressure change using only the experimental porosity formula. The area contact model was modified so that the porosity and the contact area changed with expansion and contraction. The contact area change was calculated by assuming a simple geometrical deformation caused the difference between the particle expansion and the packed bed expansion. The calculation results of the improved area contact model with the deformed factor and the shape factor were in good agreement with the reported experimental data. This calculation method of the effective thermal conductivity with the influence of expansion and contraction is expected to be useful for designing of heat transfer enhancement of a hydrogen storage tank.

It is still difficult to determine the appropriate timing of surgery for a symptomatic abdominal aortic aneurysm (AAA). Since recent developments in computed tomography (CT) have made the procedure substantially less time-consuming, we used CT on patients with symptomatic AAA to determine the most appropriate management option. CT was performed on 79 patients with symptomatic AAA. If rupture of the AAA was confirmed by CT, patients underwent emergency surgery. If there was no rupture, patients were observed in an intensive care unit, and surgery was scheduled according to the results of repeated CT (2.1 times on average) and physical examinations, as well as on their clinical signs and symptoms. By CT, we identified 42 ruptures, one contained rupture, one aortocaval fistula, five acute aortic dissections with AAAs, six inflammatory AAAs, six pseudoaneurysms and 18 non-ruptured AAAs. The mortality rate of the patients with ruptures was 33 %. For the 37 patients without rupture, as determined by CT, three emergency, nine urgent, and 20 elective operations were performed. Two patients who refused surgery experienced late rupture and died. Among the other 35 patients, the mortality rate was 6 %. CT was an effective modality to classify patients with symptomatic AAA into those who needed emergency surgery and those who did not. We could observe patients with symptomatic non-ruptured AAAs before urgent/elective operations by repeated CT and monitor the clinical findings.

Irreversible electroporation (IRE) is attracting much attention as a less-invasive therapy to ablate abnormal tissues. With a pair of electrodes inserted into the tissue, the IRE perforates the targeted cells non-thermally by a train of intensive electric pulses that exceeds a certain threshold. Since only the cells are necrotized percutaneously, the extracellular matrix is kept intact in the IRE, which is favorable for prompt tissue regeneration. In this study, we demonstrated that the IRE is also applicable to treat superficial targets such as melanoma, nevus, and tumors on gastrointestinal surface. A pair of 1-mm dia. stainless steel rods fixed 5 mm apart in an acrylic plate was contacted on an agarose gel containing fibroblasts. A sequence of 15 to 90 pulses of 1 kV was then applied to the gel via electrodes. All pulses were 10 μs in length and oscillated at 100 ms intervals. The boundary between dead and alive cell regions was determined at the surface and vertical cross section by using fluorescent staining. The necrotic cell area was also predicted by a numerical solution to the equation of electric field. Those determined with an assumption that the potential difference of 1 V between the cell membrane induces irreversible cell breakdown agreed well with the necrotic cell area and maximal depth in the experiment at low pulse number. However, the experiment showed the increase in the necrotic area with increasing the pulse repetition. Since application of multiple pulses perforates the highly resistive cell membrane, our study indicated the importance of taking into account the change in the electrical properties due to cell destruction.

To outline our experience with hepatectomy with simultaneous resection of the portal vein and hepatic artery for advanced perihilar cholangiocarcinoma, and to discuss the clinical significance of this challenging hepatectomy.Only a few authors reported negative results for this surgery in a very limited number of patients.We retrospectively reviewed medical records of 50 patients with advanced cholangiocarcinoma who underwent hepatectomy (left trisectionectomy in 26, left hepatectomy in 23, and right hepatectomy in 1) with simultaneous resection and reconstruction of the portal vein and hepatic artery, focusing on surgical outcome and survival.The operative time was 776 +/- 191 minutes, and blood loss was 2593 +/- 1890 mL. Time of vessel resection and reconstruction was 25 +/- 19 minutes for the portal vein and 119 +/- 56 minutes for the hepatic artery. A total of 27 (54.0%) patients developed several kinds of complications, including intra-abdominal abscess (n = 13), wound infection (n = 9), bile leakage from liver stump (n = 9), and liver failure (n = 7). Relaparotomy was necessary in 5 (10.0%) patients. One (2.0%) patient died of a postoperative complication. Microscopic cancer invasion of the resected portal vein was found in 44 (88.0%) patients, while that of the resected hepatic artery was found in 27 (54.0%). The distal bile duct margin, proximal bile duct margin, and radial margin were positive for cancer in 2 (4.0%), 4 (8.0%), and 17 (34.0%) patients, respectively. Consequently, R0 resection was achieved in 33 (66.0%) patients. The 1-, 3-, and 5-year survival rates were 78.9%, 36.3%, and 30.3%, respectively. Survival for 30 patients with pM0 disease who underwent R0 resection was better, being 40.7% at the 3- and 5-year time points.Major hepatectomy with simultaneous resection and reconstruction of the portal vein and hepatic artery is technically demanding. However, this surgery can be performed with acceptable mortality by an experienced surgeon and offers a better chance of long-term survival in selected patients.

To assess the reliability of the oscillometric method in patients with peripheral vascular disease, ankle blood pressure measurement by Doppler and oscillometry was compared. This study represents a prospective, non-blinded examination of pressure measurements in 168 patients. Twenty-two patients were included who had abdominal aortic aneurysms (AAA) and 146 had peripheral arterial occlusive disease (PAOD). Patients with PAOD were divided into 2 groups according to angiography results: a crural artery occlusion group (CAO, n = 32), and a no crural artery occlusion group (NCAO, n = 114). All subjects underwent pressure measurement by both Doppler and oscillometry. The correlation coefficient was 0.928 in AAA patients and 0.922 in PAOD patients. In CAO patients, there were significantly fewer patients whose oscillometric pressure was equivalent to the Doppler pressure (DP), as compared to NCAO patients, because the oscillometric pressure (OP) was 10% higher than DP in 44% of CAO patients. A high correlation exists between Doppler and oscillometric ankle pressure measurements irrespective of the type of vascular disease. However, the oscillometric method could not be substituted for the Doppler method completely, because there were several patients whose OP was greater than DP especially in those with crural artery occlusive disease.

The imaging features of an atypically enhanced hepatic hemangioma have not been well described in the literature, and the presence of such atypia may sometimes cause clinical problems in the differential diagnosis. Herein, we report a case of hepatic hemangioma demonstrating a previously unreported atypical enhancement pattern. On dynamic computed tomography during hepatic arteriography, a centrifugal enhancement pattern and subsequent peritumoral ring-shaped enhancement mimicking corona enhancement were found in cavernous hemangiomas of the liver in a 68-year-old Japanese man. Histopathological diagnosis of cavernous hemangioma of the liver was made on a biopsy specimen. Considering the importance of differentiating benign hepatic tumor from various forms of malignancy, radiologists and hepatologists should be aware of rare enhancement patterns sometimes seen in hepatic hemangioma. Establishing knowledge of the entire spectrum of atypical hepatic hemangioma may benefit the rational approach to future cases.

To date, the presence of amyloidosis associated with immunoglobulin heavy chain (AH amyloidosis) was reported in only 7 cases. Although AH amyloidosis is caused mainly by plasma cell dyscrasia, as in AL amyloidosis, we report a 61-year-old patient who presented with nephrotic syndrome caused by AH amyloidosis associated with lymphoplasmacytic lymphoma. Biochemical and molecular analyses of the deposited amyloid fibrils and heavy-chain genes of lymphocytes showed that proliferative lymphoma cells produced a gamma heavy chain, not a mu heavy chain, which carried an unusual truncated diversity (D) segment of the variable region. Our results indicate that production of the abnormal heavy chain caused by the partially deleted D segment gene is responsible for gamma heavy-chain-related amyloid fibril formation in this patient.

This paper presents the effects of the cross-sectional in-plane crystal orientation (θ) on the structural strength of single crystal turbine vanes using the finite element method (FEM). The material of the turbine vanes is the single crystal superalloy TMS-75. The obtained results show that the elastic constant matrix (c'44) changes were by above 60% due to the orientation variation (0° < θ < 90°). The dependency of the structural strength of the turbine vane on the crystal orientation was calculated using von Mises stress equation. The strength of the turbine vane was strongly related to θ, and also related to the model shape and load. This influence becomes more significant near the leading edge of the turbine vane where it is most likely to fracture.

症例は80歳,女性で, 40年前に子宮内避妊具 (IUD: intrauterine device) を留置されていた.下腹部痛および嘔吐を主訴に入院し,イレウスの診断にて,保存的治療が開始された.第2病日の腹部CT検査にて,絞掘性イレウスと診断し緊急手術を施行した.開腹したところ,子宮底部から穿孔したIUD (太田リング)が一部腹腔内へ脱出していた.索状物が子宮底部のIUDとS状結腸壁の間に形成され,回腸を絞扼していた.壊死部をふくむ約60cmの回腸を切除し,吻合した.術後19日目に軽快退院した. IUDが絞掘性イレウスの原因となった本邦報告1例目と思われる稀な症例を経験したので文献的考察を加え報告する.

Purpose. Abdominal aortic aneurysm (AAA) usually is associated with atherosclerosis. We attempted to create an abdominal aortic aneurysm with atherosclerotic plaque in rabbits to investigate the relationship between atherosclerosis and enlargement of AAA. Methods. An isolated segment of rabbit abdominal aorta was perfused with pancreatic elastase. Animals were fed a cholesterol-enriched diet to induce atherosclerotic plaque formation. Eight animals received perfusion with elastase and were fed a cholesterol-enriched diet (group EC), eight animals received perfusion with elastase and were fed a normal diet (group EN), eight animals received perfusion with saline and were fed a cholesterol-enriched diet (group SC), and eight animals received perfusion with saline and were fed a normal diet (group SN). Four animals served as a sham group. Each animal was killed after aortography at 4 or 12 weeks. The perfused segment was excised and examined histologically. Results. No animal treated with saline and fed normal diet (groups SN) developed either an aneurysm or atherosclerosis. Atherosclerotic plaque was observed in animals fed the cholesterol-enriched diet (groups SC and EC) at 4 weeks, and the plaque had thickened further by 12 weeks. All animals treated with elastase (groups EN and EC) developed an AAA. Maximum internal diameter in groups EN and EC (4.1 mm) was equal at 4 weeks, but at 12 weeks, the diameter was less for group EC than for group EN (4.0 mm versus 4.8 mm, P

A 19-year-old female college student had numbness and the sensation of coldness of her left toes. She had a 3-year smoking history. Gangrene of the left foot developed rapidly. Angiography revealed peripheral arterial occlusion of both legs and arms. Detailed laboratory examination excluded collagen disease, a hypercoagulable state, and juvenile atherosclerosis. Below-knee amputation of the left leg was performed. Typical histologic findings of Buerger’s disease were observed in the crural arteries and saphenous veins. The clinical course was uneventful after the patient stopped smoking. This is the second case report of Buerger’s disease in a woman in the second decade of life. It is important that a correct diagnosis of Buerger’s disease be established, because the disease process is benign, compared with collagen disease, if the patient stops smoking.

This paper presents an investigation into the expression of endothelial cells and vascular endothelial growth factor (VEGF) in the aortic wall in vascular diseases such as atherosclerotic abdominal aortic aneurysm (AAAA), inflammatory abdominal aortic aneurysm (IAAA), and aortic occlusive disease (AOD) to determine whether the differences in both neovascularization and angiogenic factor expression are related to the pathogenesis of aortic vascular disease.Surgical specimens of aorta (10 IAAA, 13 AAAA, 6 AOD) were studied pathologically and immunohistochemically. Representative sections of aorta were stained with hematoxylin-eosin, elastica von Gieson, CD34, and VEGF antibody. CD34-positive microvessels and VEGF-positive cells in the media and adventitia were counted, respectively.CD34-positive microvessels were detected in IAAAAAAAAOD (one-way analysis of variance (ANOVA), P0.0001). VEGF expression was widely detected in macrophages, monocytes, and smooth muscle cells of IAAA and AAAA; however, it was hardly recognized in AOD. VEGF-positive cells were detected in IAAAAAAAAOD specimens (ANOVA, P0.0001).VEGF is known to be a regulator of angiogenesis and to simultaneously stimulate elastolytic proteinases. The results of this study suggest that an angiogenic factor, such as VEGF, may play an important role in the degeneration of the aortic wall and could be strongly related to the pathogenesis of IAAA, AAAA, and AOD.

We performed descending thoracic aortic repair via posterolateral thoracotomy using retrograde cerebral perfusion with direct cannulation into the left internal jugular vein. No postoperative neurological dysfunction was observed. This patient was discharged without any adverse events.

Purpose: Limb-sparing procedures have recently replaced amputations as the treatment for tumors invading major vessels of the lower extremity. Major arteries must be reconstructed for limb salvage. The veins are not usually reconstructed. This study was undertaken to investigate the sequelae such as chronic venous disease after venous resection for tumors. Methods: Ten patients who underwent limb-sparing surgery for a tumor of the lower extremity or retroperitoneum that required major vascular resection were studied. The median follow-up period was 48 months. After combined resection of a major artery and vein, arterial reconstruction was performed. The veins were not reconstructed. The resected veins included the inferior vena cava (n = 2), the external iliac and common femoral veins (n = 3), the superficial femoral vein (n = 3), and the popliteal vein (n = 2). The main outcome measures were clinical classification of chronic venous disease in 10 patients and air plethysmography in seven patients. Results: Clinical classification was C 0A in 6 patients, C 3A in 1 patient, C 3S in 2 patients, and C 4S in 1 patient. Venous claudication with uncontrollable edema was observed in two patients with C 3S disease. Pain and itching with inflammatory skin changes were observed in one patient with C 4S disease. These three patients had undergone resection of the femoral vein, including the deep femoral vein along with proximal adductor muscles. Air plethysmography revealed that the ejection fraction was significantly lower and the residual volume fraction was significantly higher in the three patients with symptoms than in symptom-free patients. Conclusions: Significant chronic venous disease was observed in the patients who underwent combined resection of the femoral vein, the deep femoral vein, and the adductor muscles for a tumor. (J Vasc Surg 2001;33:694-9.)

Background and Objective Advantages of laser-welded microarterial anastomoses have been reported. However, whether laser repair of large veins is advantageous is not yet known. Argon-laser welding of inferior vena cava was therefore compared with conventional-sutured repair. Study Design/Materials and Methods Twenty-four adult mongrel dogs were used. Twelve inferior vena cavas were repaired using an argon laser and the rest using continuous sutures. Specimens were removed at 2, 8, 16, and 24 weeks after repair. Technical characteristics, cavographical findings, and results of histopathological study using light and transmission electron microscopy were compared. Results Procedure time did not significantly differ between the two groups. The sutured repair sites were narrower than those repaired by laser immediately after and at 2 and 24 weeks. Histologically, laser welding resulted from denaturation of collagen and mild healing occurred simultaneously with the disappearance of denatured collagen. By contrast, there was strong fibrotic reaction at sutured repair sites. Conclusions These findings suggest that argon-laser repair of large veins is superior to continuous suturing. Lasers Surg. Med. 29:62–69, 2001. © 2001 Wiley-Liss, Inc.

A 13-year-old boy with a solitary exostosis of the left femur was seen with a pseudo-aneurysm of the popliteal artery. When left leg pain occurred 3 months earlier, radiographic examination revealed an exostosis with a cartilage cap. Serial radiographic examination demonstrated gradual disruption of the cartilage cap of the exostosis as the pseudoaneurysm developed. An exostosis with an irregular surface was found at surgery. A literature review disclosed 39 similar cases in which loss of the cartilage cap was considered as one of the causes of the aneurysm formation. Considering the clinical course of our patient, however, we believe that exostoses lose their cartilage caps by pressure destruction due to the aneurysms. It is highly probable that loss of the cartilage does not cause the aneurysms. (J Vasc Surg 2000;32:201-4.)

Purpose: Intermittent claudication can be regarded as repeated ischemia reperfusion injury, which can induce a generalized increase in vascular permeability, including in intestine. The lactulose mannitol test (L/M test) was performed in patients with intermittent claudication to evaluate the change in intestinal permeability when they were forced to walk. Methods: The L/M test was performed in 11 patients with intermittent claudication and 11 control subjects without intermittent claudication. The test was performed at rest and after exercise. Patients walked on a treadmill until they stopped because of pain. The control subjects were forced to walk as far as 200 m on a treadmill. The L/M test was repeated in the patients after successful arterial reconstruction. Then the patients were instructed to walk the same distance at the same speed as they had before surgery. Results: In patients, the mean L/M ratio after exercise was significantly higher than the mean L/M ratio when they were at rest (0.068 ± 0.053 vs 0.022 ± 0.009, P